1 /* File descriptor related functions.
2 
3    Copyright (C) 2019-2020 Free Software Foundation, Inc.
4 
5    This file is part of the libiberty library.
6 
7    This program is free software; you can redistribute it and/or modify
8    it under the terms of the GNU General Public License as published by
9    the Free Software Foundation; either version 2 of the License, or
10    (at your option) any later version.
11 
12    This program is distributed in the hope that it will be useful,
13    but WITHOUT ANY WARRANTY; without even the implied warranty of
14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15    GNU General Public License for more details.
16 
17    You should have received a copy of the GNU General Public License
18    along with this program; if not, write to the Free Software
19    Foundation, Inc., 51 Franklin Street - Fifth Floor,
20    Boston, MA 02110-1301, USA.  */
21 
22 #include "config.h"
23 #include "ansidecl.h"
24 #include "libiberty.h"
25 
26 #ifdef HAVE_FCNTL_H
27 #include <fcntl.h>
28 #endif
29 
30 #if defined (_WIN32)
31 #define WIN32_LEAN_AND_MEAN
32 #include <windows.h> /* for GetFullPathName */
33 #endif
34 /* Return true when FD file descriptor exists.  */
35 
36 int
37 is_valid_fd (int fd)
38 {
39 #if defined(_WIN32)
40   HANDLE h = (HANDLE) _get_osfhandle (fd);
41   return h != (HANDLE) -1;
42 #elif defined(F_GETFD)
43   return fcntl (fd, F_GETFD) >= 0;
44 #else
45   return dup2 (fd, fd) < 0;
46 #endif
47 }
48